Survival of follicles was spatially related to presence of pericytes rather than to endothelial cells in the area of the graft (Fig. 1, G-I; Fig. 2, A-O; Fig. 3, G-R). The ovarian cortex showed better follicular maintenance, probably due to sufficient blood supply (see Fig. 1I). Interestingly, Dissen et al. showed that the mRNA expression of the two angiogenic factors, VEGF and TGFp-1, is upregulated mainly at the ovarian cortex 48 h after transplantation. In the subcutaneous implants, no recovery of the initial damage was observed, whereas in the intramuscular grafts, improvement was observed within 6-7 days postimplantation, showing healthy follicular morphology and vascular integrity, including endothelial cells, pericytes, and SMC.
Vascular permeability in the implanted ovaries was studied by MRI and by histology. In muscle, the contrast material was restricted to the blood vessel lumen, whereas in the ovary, it was found to extravasate to the surrounding tissue. Shalgi et al. showed that the permeability of the blood follicle barrier to serum proteins is inversely related to their molecular weight and smaller proteins like albumin are found at higher concentration in follicular fluid than in the serum. Such hyperpermeability is a well-known characteristic of the ovarian vasculature and was also demonstrated here for the intact normal ovary as well as the transplanted ovary. ventolin inhaler
In conclusion, we report here that survival of ovarian implants was improved under conditions that support vascular maintenance. Thus, follicular integrity was associated with preservation of pericyte coating while loss of aSMA was reflected by follicular damage. Subcutaneous implantation was followed by pericyte loss associated with tissue damage, whereas intramuscular transplantation showed vascular maintenance and was associated with improved follicular preservation.